Conventionally, when a panel is constructed as a door panel 1' for a vehicle, as shown in FIG. 8, a first flange 3' formed on the upper edge of an inner panel 2' and a second flange 5' formed on the upper edge of an outer panel 4' are joined by spot welding 7'. Then, as shown in FIGS. 9(A) and 9(B), a trim member (called weatherstrip, molding or welt) 11' is mounted on the edges (upper ends) of the joined first and second flanges 3' and 5' as the latter flanges 3' and 5' are inserted into an insertion groove formed on the trim member 11'.
Such a trim member 11' is disclosed in Japanese Laid-Open Patent Publication No. 2-68240, for example.
When the first flange 3' of the inner panel 2' is joined to the second flange 5' of the outer panel 4', the joined flanges 3' and 5' may sometimes be joined with their position shifted in a vertical direction, as shown in FIG. 8, or the joined flanges 3' and 5' may sometimes be joined with their upper ends partly opened, as shown in FIG. 10.
When the first and the second flanges 3' and 5' are joined with their position shifted in a vertical direction as shown in FIG. 8, in the mounting position shown in FIG. 9(B) where the upper ends of the joined flanges 3' and 5' are inserted into the trim member 11', a distance H' required between a reference position of the door panel 1', such as a center P' of a through hole 6 formed through the outer panel 4', and the upper edge of the trim member 11' is increased by the amount L' corresponding to the above-noted shift of position. As a result, there arise problems that the trim member 11' is mounted obliquely relative to the upper edge of the joined flanges 3' and 5', or that the trim member 11' interferes with other parts assembled therearound, such as a door glass.
When the flanges 3' and 5' are joined with the upper ends partly opened, as shown in FIGS. 10 and 11, it is difficult to insert the upper ends of the flanges 3' and 5' into the trim member 11', and additionally, the insertion groove of the trim member 11' remains open, thus impairing appearance of the mounted trim member 11'.
In case of a panel 101' forming a wheel arch section for a vehicle, as shown in FIGS. 12 and 13(A) to 13(C), a flange 103' formed by bending the panel 101' along the wheel arch section is inserted into an insertion groove formed on a trim member 111'. In this case, the distance from the bend to the edge of the flange 103' tends to vary to be slightly larger or smaller than a normal distance S, or the bending angle tends to vary to be larger or smaller than a normal angle .theta.. As a result, the trim member 111' cannot be mounted in a desired condition, and appearance of the mounted trim member 111' is impaired.